:root {
    --background: #0B1121;
    --background-blur: rgba(11, 17, 33, 0.85);
    --blue: #3B82F6;
    --blue-light: #60A5FA;
    --blue-dark: #1D4ED8;
    --primary: #3B82F6;
    --primary-hover: #2563EB;
    --border: #1E293B;
    --border-light: #334155;
    --text: #FFFFFF;
    --text-secondary: #94A3B8;
    --text-muted: #64748B;
    --shadow: rgba(0, 0, 0, 0.25);
    --gradient: linear-gradient(135deg, #3B82F6 0%, #1D4ED8 100%);
    --glow: 0 0 20px rgba(59, 130, 246, 0.3);
}

html {
    scroll-behavior: smooth;
    scrollbar-width: thin!important; /* Chrome, Edge et Firefox */
    scrollbar-gutter: stable !important; /* Chrome, Edge et Firefox */
    scrollbar-color: var(--background) var(--blue-opac)!important; /* Chrome, Edge et Firefox */
    overflow-x: hidden;
    width: 100vw;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    width: 100vw;
    scroll-behavior: smooth;
    scrollbar-width: thin!important; /* Chrome, Edge et Firefox */
    scrollbar-gutter: stable !important; /* Chrome, Edge et Firefox */
    scrollbar-color: var(--background) var(--blue-opac)!important; /* Chrome, Edge et Firefox */

}

header {
    position: sticky;
    top: 0;
    width: 100vw;
    border-bottom: 1px solid var(--border);
    background: var(--background-blur);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    z-index: 1000;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.24);
}

header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--blue), transparent);
    opacity: 0.6;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
    position: relative;
    gap: 0.5rem;
}

.logo-nav {
    display: flex;
    align-items: center;
    gap: 3rem;
    flex: 1;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    color: var(--text);
    font-weight: 700;
    font-size: 1.25rem;
    transition: all 0.3s ease;
    position: relative;
}

.logo:hover {
    transform: translateY(-1px);
}

.logo-circle {
    width: 4rem;
    height: 4rem;
    background: transparent;
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0.2rem;
    box-shadow: 0 4px 12px rgba(25, 49, 109, 0.2);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    cursor: pointer;
}

.logo-circle img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    transition: transform 0.3s ease;
}

.logo-circle::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transform: rotate(45deg);
    transition: all 0.6s ease;
    opacity: 0;
}

.logo:hover .logo-circle {
    transform: rotate(5deg) scale(1.05);
    box-shadow: var(--glow);
}

.logo:hover .logo-circle::before {
    opacity: 1;
    transform: rotate(45deg) translate(50%, 50%);
}

/* Navigation principale */
nav {
    display: flex;
    align-items: center;
    gap: 2.5rem;
}

nav a {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    justify-content: center;
    flex-direction: row;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    white-space: nowrap;
}

nav a::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--gradient);
    transition: all 0.3s ease;
    transform: translateX(-50%);
}

nav a:hover {
    color: var(--text);
    background: rgba(59, 130, 246, 0.1);
    transform: translateY(-1px);
}

nav a:hover::before {
    width: 80%;
}

nav a.active {
    color: var(--blue-light);
    background: rgba(59, 130, 246, 0.15);
}

nav a.active::before {
    width: 80%;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.notification-btn {
    background: none;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0.75rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.notification-btn:hover {
    color: var(--text);
    background: rgba(59, 130, 246, 0.1);
    transform: translateY(-1px);
}

.start-challenge {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    width: fit-content;
    flex-direction: row;
    background: var(--gradient);
    color: white;
    border: none;
    padding: 0.75rem 1.5rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
    position: relative;
    overflow: hidden;
    white-space: nowrap;
}

.start-challenge::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.6s ease;
}

.start-challenge:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
    background: linear-gradient(135deg, var(--blue-light) 0%, var(--blue) 100%);
}

.start-challenge:hover::before {
    left: 100%;
}

.start-challenge:active {
    transform: translateY(0);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 1001;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    border-radius: 8px;
    transition: all 0.3s ease;
}

.mobile-menu-btn:hover {
    background: rgba(59, 130, 246, 0.1);
}

.mobile-menu-btn span {
    display: block;
    width: 22px;
    height: 2px;
    background-color: var(--text);
    margin: 3px 0;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    border-radius: 1px;
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
    transform: scale(0);
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(11, 17, 33, 0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 5rem 2rem 2rem;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.mobile-menu.active {
    display: flex;
    flex-direction: column;
    opacity: 1;
    visibility: visible;
}

.mobile-menu ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.mobile-menu li {
    margin: 0;
    opacity: 0;
    transform: translateX(-30px);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.mobile-menu.active li {
    opacity: 1;
    transform: translateX(0);
}

.mobile-menu.active li:nth-child(1) { transition-delay: 0.1s; }
.mobile-menu.active li:nth-child(2) { transition-delay: 0.15s; }
.mobile-menu.active li:nth-child(3) { transition-delay: 0.2s; }
.mobile-menu.active li:nth-child(4) { transition-delay: 0.25s; }

.mobile-menu a {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-direction: row;
    padding: 1rem 1.5rem;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 1.1rem;
    font-weight: 500;
    border-radius: 12px;
    transition: all 0.3s ease;
    border: 1px solid transparent;
}

.mobile-menu a:hover, .mobile-menu a.active {
    color: var(--text);
    background: rgba(59, 130, 246, 0.1);
    border-color: rgba(59, 130, 246, 0.2);
    transform: translateX(8px);
}

.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.fade-out {
    opacity: 1;
    transform: translateY(0);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-out.visible {
    opacity: 0;
    transform: translateY(30px);
}

.fade-in-left {
    opacity: 0;
    transform: translateX(-50px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-in-left.visible {
    opacity: 1;
    transform: translateX(0);
}

.fade-in-right {
    opacity: 0;
    transform: translateX(50px);
    transition: all 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-in-right.visible {
    opacity: 1;
    transform: translateX(0);
}

@media screen and (min-width: 1400px) {
    .header-container {
        padding: 0 3rem;
    }
    
    .logo-nav {
        gap: 4rem;
    }
    
    nav {
        gap: 3rem;
    }
}

@media screen and (min-width: 1025px) and (max-width: 1399px) {
    .header-container {
        padding: 0 2rem;
    }
    
    .header-nav{
        font-size: 0.8rem;
        gap: 0.5rem;
    }
    
    .logo-nav {
        gap: 1rem;
    }
    
    nav {
        gap: 0.5rem;
    }

    .start-challenge {
        padding: 0.6rem 1.2rem;
        font-size: 0.8rem;
    }
}

@media screen and (min-width: 866px) and (max-width: 1024px) {
    .header-container {
        padding: 0 1.5rem;
        height: 65px;
    }

    .logo-circle{
        width: 6rem;
        font-size: 90%;
    }

    .header-nav{
        gap: 0.3rem;
    }
    
    .logo-nav {
        gap: 1rem;
    }

    .notification-btn{
        padding: 0.5rem;
    }

    .header-actions{
        gap: 0.3rem;
    }
    
    nav {
        gap: 0.5rem;
    }
    
    nav a {
        font-size: 0.8rem;
        padding: 0.4rem 0.8rem;
    }
    
    .start-challenge {
        padding: 0.4rem 1rem;
        font-size: 0.7rem;
    }
}

@media screen and (min-width: 481px) and (max-width: 865px) {
    .header-container {
        padding: 0 2rem;
        height: 60px;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .logo-nav {
        justify-content: flex-start;
        gap: 0;
    }
    
    nav {
        display: none;
    }
    
    .header-actions {
        gap: 0.75rem;
    }
    
    .start-challenge {
        padding: 0.6rem 0.8rem;
        font-size: 0.7rem;
    }
    
    .logo {
        font-size: 1rem;
    }
    
    .logo-circle {
        font-size: 0.8rem;
    }
}

@media screen and (max-width: 480px) {
    .header-container {
        padding: 0 1rem;
        height: 55px;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .logo-nav {
        justify-content: flex-start;
        gap: 0;
    }
    
    nav {
        display: none;
    }
    
    .header-actions {
        gap: 0.5rem;
    }
    
    .notification-btn {
        display: none; /* Cache sur très petits écrans */
    }
    
    .start-challenge {
        padding: 0.4rem 0.6rem;
        font-size: 0.7rem;
        white-space: nowrap;
    }
    
    .logo {
        font-size: 0.8rem;
        gap: 0.5rem;
    }
    
    .logo-circle {
        width: 66px;
        font-size: 0.7rem;
    }
    
    .mobile-menu {
        padding: 4rem 1rem 2rem;
    }
    
    .mobile-menu a {
        font-size: 0.4rem;
        padding: 0.8rem 1rem;
    }
}

@media screen and (max-width: 320px) {
    .header-container {
        padding: 0 0.75rem;
    }
    
    .start-challenge {
        padding: 0.4rem 0.6rem;
        font-size: 0.7rem;
    }
    
    .logo {
        font-size: 0.6rem;
    }
    
    .logo-circle {
        width: 46px;
        font-size: 0.75rem;
    }
}

@media screen and (min-width: 1025px) {
    header:hover {
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    }
    
    .header-container::after {
        content: '';
        position: absolute;
        bottom: -1px;
        left: 0;
        right: 0;
        height: 1px;
        background: linear-gradient(90deg, transparent, var(--blue-light), transparent);
        opacity: 0;
        transition: opacity 0.3s ease;
    }
    
    header:hover .header-container::after {
        opacity: 0.8;
    }
}

/* Performance optimizations */
* {
    will-change: auto;
}

.logo-circle,
.start-challenge,
nav a,
.mobile-menu-btn {
    will-change: transform;
}

/* Accessibilité */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus styles pour l'accessibilité */
.start-challenge:focus,
nav a:focus,
.mobile-menu a:focus,
.mobile-menu-btn:focus {
    outline: 2px solid var(--blue);
    outline-offset: 2px;
}

/* Styles des boutons */
.btn-primary {
    position: relative;
    padding: 16px 32px;
    font-size: 16px;
    font-weight: 600;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    overflow: hidden;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    min-height: 56px;
}

@media screen and (max-width: 768px) {
    .btn-primary {
        width: 100%;
        font-size: 0.8rem;
        font-weight: 500;
        padding: 0.5rem 1rem;
        min-height: 48px;
    }
}

.btn-startchallenge {
    background: linear-gradient(135deg, #1e40af 0%, #3b82f6 50%, #06b6d4 100%);
    color: white;
    box-shadow: 0 8px 32px rgba(59, 130, 246, 0.3);
}

.btn-startchallenge::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.6s ease;
}

.btn-startchallenge:hover::before {
    left: 100%;
}

.btn-startchallenge:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(59, 130, 246, 0.4);
    background: linear-gradient(135deg, var(--blue-light) 0%, var(--blue) 100%);
}

.btn-startchallenge:active {
    transform: translateY(0);
}

.btn-cyber {
    background: linear-gradient(135deg, #0ea5e9 0%, #3b82f6 50%, #6366f1 100%);
    color: white;
    border: 1px solid rgba(59, 130, 246, 0.3);
    position: relative;
    overflow: hidden;
}

.btn-cyber::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, transparent 30%, rgba(255, 255, 255, 0.1) 50%, transparent 70%);
    transform: translateX(-100%);
    transition: transform 0.6s;
}

.btn-cyber:hover::after {
    transform: translateX(100%);
}

.btn-cyber:hover {
    box-shadow: 0 0 30px rgba(59, 130, 246, 0.6), inset 0 0 20px rgba(255, 255, 255, 0.1);
    transform: translateY(-3px);
}

.btn-neon {
    background: linear-gradient(135deg, #1e3a8a 0%, #3b82f6 100%);
    color: #00d4ff;
    border: 2px solid #00d4ff;
    text-shadow: 0 0 10px #00d4ff;
    box-shadow: 
        0 0 20px rgba(0, 212, 255, 0.3),
        inset 0 0 20px rgba(0, 212, 255, 0.1);
}

.btn-neon:hover {
    background: linear-gradient(135deg, #3b82f6 0%, #00d4ff 100%);
    color: #1e3a8a;
    text-shadow: none;
    box-shadow: 
        0 0 40px rgba(0, 212, 255, 0.8),
        inset 0 0 30px rgba(255, 255, 255, 0.2);
    transform: scale(1.05);
}

/* === BOUTONS STANDARDS === */
.btn-standard {
    background: linear-gradient(135deg, #374151 0%, #4b5563 100%);
    color: #f9fafb;
    border: 1px solid rgba(255, 255, 255, 0.1);
}


.btn-standard:hover {
    background: linear-gradient(135deg, #4b5563 0%, #6b7280 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

.btn-ghost {
    background: transparent;
    color: #e5e7eb;
    border: 2px solid rgba(229, 231, 235, 0.3);
    backdrop-filter: blur(10px);
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(229, 231, 235, 0.6);
    backdrop-filter: blur(20px);
    transform: translateY(-2px);
}

.btn-gradient {
    background: linear-gradient(135deg, #6b7280 0%, #9ca3af 50%, #d1d5db 100%);
    color: #1f2937;
    border: none;
}

.btn-gradient:hover {
    background: linear-gradient(135deg, #9ca3af 0%, #d1d5db 50%, #f3f4f6 100%);
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
}

.btn-tech {
    background: linear-gradient(135deg, #111827 0%, #374151 100%);
    color: #10b981;
    border: 1px solid #10b981;
    position: relative;
}

.btn-tech::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, transparent, rgba(16, 185, 129, 0.1));
    opacity: 0;
    transition: opacity 0.3s;
}

.btn-tech:hover::before {
    opacity: 1;
}

.btn-tech:hover {
    box-shadow: 0 0 25px rgba(16, 185, 129, 0.4);
    transform: translateY(-2px);
}

/* === NOUVEAUX STYLES PARTICIPATION === */
.btn-participate {
    background: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 50%, #1e40af 100%);
    color: white;
    box-shadow: 0 8px 32px rgba(59, 130, 246, 0.4);
    position: relative;
}

.btn-participate::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: radial-gradient(circle, rgba(255,255,255,0.3) 0%, transparent 70%);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: all 0.5s ease;
}

.btn-participate:hover::after {
    width: 300px;
    height: 300px;
}

.btn-participate:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 15px 40px rgba(59, 130, 246, 0.5);
}

.btn-register {
    background: linear-gradient(135deg, #059669 0%, #10b981 50%, #34d399 100%);
    color: white;
    border: 2px solid transparent;
    background-clip: padding-box;
}

.btn-register:hover {
    background: linear-gradient(135deg, #10b981 0%, #34d399 50%, #6ee7b7 100%);
    transform: translateY(-2px);
    box-shadow: 0 10px 35px rgba(16, 185, 129, 0.4);
}

.btn-compete {
    background: linear-gradient(135deg, #dc2626 0%, #ef4444 50%, #f87171 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.btn-compete::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 10px,
        rgba(255,255,255,0.1) 10px,
        rgba(255,255,255,0.1) 20px
    );
    animation: stripes 2s linear infinite;
}

@keyframes stripes {
    0% { transform: translateX(-20px); }
    100% { transform: translateX(20px); }
}

.btn-compete:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 40px rgba(220, 38, 38, 0.4);
}

.btn-hackathon {
    background: linear-gradient(135deg, #7c3aed 0%, #a855f7 50%, #c084fc 100%);
    color: white;
    box-shadow: 0 8px 32px rgba(124, 58, 237, 0.3);
}

.btn-hackathon:hover {
    background: linear-gradient(135deg, #a855f7 0%, #c084fc 50%, #ddd6fe 100%);
    transform: translateY(-2px) rotateZ(1deg);
    box-shadow: 0 15px 45px rgba(124, 58, 237, 0.5);
}

/* === STYLES ACTIONS SPÉCIALES === */
.btn-stream {
    background: linear-gradient(135deg, #dc2626 0%, #ef4444 100%);
    color: white;
    animation: pulse-red 2s infinite;
}

@keyframes pulse-red {
    0%, 100% { box-shadow: 0 0 20px rgba(220, 38, 38, 0.4); }
    50% { box-shadow: 0 0 40px rgba(220, 38, 38, 0.8); }
}

.btn-stream:hover {
    transform: scale(1.05);
    animation: none;
    box-shadow: 0 0 50px rgba(220, 38, 38, 0.9);
}

.btn-mentor {
    background: linear-gradient(135deg, #0891b2 0%, #06b6d4 50%, #22d3ee 100%);
    color: white;
    position: relative;
}

.btn-mentor::before {
    content: '💬';
    position: absolute;
    top: -10px;
    right: -10px;
    background: #10b981;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 10px;
    animation: bounce 1s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

.btn-mentor:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 35px rgba(8, 145, 178, 0.4);
}

.btn-workshop {
    background: linear-gradient(135deg, #ea580c 0%, #f97316 50%, #fb923c 100%);
    color: white;
}

.btn-workshop:hover {
    background: linear-gradient(135deg, #f97316 0%, #fb923c 50%, #fed7aa 100%);
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(234, 88, 12, 0.4);
}

.btn-github {
    background: linear-gradient(135deg, #374151 0%, #4b5563 50%, #6b7280 100%);
    color: white;
    border: 1px solid #d1d5db;
}

.btn-github:hover {
    background: linear-gradient(135deg, #1f2937 0%, #374151 50%, #4b5563 100%);
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.btn-leaderboard {
    background: linear-gradient(135deg, #facc15 0%, #eab308 50%, #ca8a04 100%);
    color: #1f2937;
    font-weight: 700;
}

.btn-leaderboard:hover {
    background: linear-gradient(135deg, #fde047 0%, #facc15 50%, #eab308 100%);
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 12px 35px rgba(250, 204, 21, 0.4);
}

.btn-team {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a855f7 100%);
    color: white;
}

.btn-team:hover {
    background: linear-gradient(135deg, #8b5cf6 0%, #a855f7 50%, #c084fc 100%);
    transform: translateY(-2px);
    box-shadow: 0 12px 35px rgba(139, 92, 246, 0.4);
}

/* Effets spéciaux */
.btn-pulse {
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { box-shadow: 0 0 20px rgba(59, 130, 246, 0.3); }
    50% { box-shadow: 0 0 40px rgba(59, 130, 246, 0.6); }
}

.btn-3d {
    transform-style: preserve-3d;
    transition: transform 0.3s;
}

.btn-3d:hover {
    transform: translateY(-5px) rotateX(10deg);
}

/* === STYLES POUR ICÔNES LUCIDE === */
.icon {
    width: 20px;
    height: 20px;
    fill: currentColor;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    transition: all 0.3s ease;
}

/* Animations spécifiques pour les icônes */
.btn-primary:hover .icon {
    transform: scale(1.1);
}

.btn-startchallenge:hover .icon,
.btn-participate:hover .icon,
.btn-hackathon:hover .icon {
    animation: iconSpin 0.6s ease-in-out;
}

.btn-stream:hover .icon {
    animation: iconPulse 0.8s infinite;
}

.btn-compete:hover .icon {
    animation: iconShake 0.5s ease-in-out;
}

.btn-neon:hover .icon {
    filter: drop-shadow(0 0 8px currentColor);
    animation: iconGlow 1s ease-in-out infinite alternate;
}

.btn-cyber:hover .icon {
    animation: iconFlicker 0.3s ease-in-out 3;
}

.btn-mentor .icon {
    animation: iconFloat 2s ease-in-out infinite;
}

.btn-github:hover .icon {
    transform: rotateY(180deg);
}

.btn-leaderboard:hover .icon {
    animation: iconBounce 0.6s ease;
}

.btn-workshop:hover .icon {
    animation: iconRotate 0.5s ease-in-out;
}

/* Animations keyframes pour les icônes */
@keyframes iconSpin {
    0% { transform: scale(1) rotate(0deg); }
    50% { transform: scale(1.2) rotate(180deg); }
    100% { transform: scale(1.1) rotate(360deg); }
}

@keyframes iconPulse {
    0%, 100% { transform: scale(1.1); }
    50% { transform: scale(1.3); }
}

@keyframes iconShake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-2px) rotate(-2deg); }
    75% { transform: translateX(2px) rotate(2deg); }
}

@keyframes iconGlow {
    0% { filter: drop-shadow(0 0 5px currentColor); }
    100% { filter: drop-shadow(0 0 15px currentColor); }
}

@keyframes iconFlicker {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

@keyframes iconFloat {
    0%, 100% { transform: translateY(0px); }
    50% { transform: translateY(-3px); }
}

@keyframes iconBounce {
    0%, 100% { transform: translateY(0); }
    25% { transform: translateY(-5px) scale(1.1); }
    50% { transform: translateY(-2px) scale(1.05); }
    75% { transform: translateY(-3px) scale(1.08); }
}

@keyframes iconRotate {
    0% { transform: rotate(0deg) scale(1.1); }
    50% { transform: rotate(180deg) scale(1.2); }
    100% { transform: rotate(360deg) scale(1.1); }
}

/* Styles spéciaux pour différents types d'icônes */
.btn-primary .icon-play {
    margin-left: 2px; /* Centrage visuel pour les triangles */
}

.btn-primary .icon-arrow {
    transition: transform 0.3s ease;
}

.btn-primary:hover .icon-arrow {
    transform: translateX(3px) scale(1.1);
}

.btn-primary .icon-star {
    filter: drop-shadow(0 0 3px rgba(255, 215, 0, 0.3));
}

.btn-primary:hover .icon-star {
    filter: drop-shadow(0 0 8px rgba(255, 215, 0, 0.6));
    animation: iconTwinkle 1s ease-in-out;
}

@keyframes iconTwinkle {
    0%, 100% { transform: scale(1.1) rotate(0deg); }
    25% { transform: scale(1.2) rotate(-5deg); }
    75% { transform: scale(1.15) rotate(5deg); }
}

/* Effets de groupe pour les icônes avec texte */
.btn-primary:hover .icon + span {
    transform: translateX(2px);
}

/* Icônes avec badges/notifications */
.btn-primary.has-notification .icon {
    position: relative;
}

.btn-primary.has-notification .icon::after {
    content: '';
    position: absolute;
    top: -2px;
    right: -2px;
    width: 8px;
    height: 8px;
    background: #ef4444;
    border-radius: 50%;
    border: 2px solid currentColor;
    animation: iconNotification 2s infinite;
}

@keyframes iconNotification {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

/* Couleurs spécifiques pour certaines icônes */
.btn-stream .icon {
    color: #ffffff;
    filter: drop-shadow(0 0 5px #ef4444);
}

.btn-github .icon {
    transition: all 0.3s ease;
}

.btn-github:hover .icon {
    color: #f0f0f0;
}

.btn-tech .icon {
    color: #10b981;
}

.btn-neon .icon {
    color: #00d4ff;
}

/* === intl-tel-input dark theme overrides === */
.iti { width: 100%; }
.iti--container { z-index: 9999; } /* ensure dropdown above modals/overflow */
.iti__country-list {
  background-color: var(--card, #0f172a) !important;
  color: var(--text, #e2e8f0) !important;
  border: 1px solid var(--border, #1f2937) !important;
  box-shadow: 0 10px 25px rgba(0,0,0,0.35) !important;
}
.iti__country-list .iti__country {
  background-color: transparent !important;
  color: var(--text, #e2e8f0) !important;
}
.iti__country-list .iti__country:hover,
.iti__country-list .iti__country[aria-selected="true"] {
  background-color: rgba(99, 102, 241, 0.15) !important; /* indigo-500/15 */
}
.iti--allow-dropdown .iti__flag-container:hover .iti__selected-flag { background-color: transparent; }
.iti__selected-flag {
  background-color: rgba(148,163,184,0.08) !important; /* slate-400/8 */
  border-radius: 8px;
  padding: 2px 6px;
}
.iti__country-name { color: inherit !important; }
.iti__dial-code { color: #94a3b8 !important; }

/* Input size alignment with your inputs */
.iti input[type="tel"],
input[type="tel"].iti__tel-input {
  background: transparent;
  color: var(--text, #e2e8f0);
}
/* === School select styling (auth form) === */
.custom-select-container .display { position: relative; }
.school-select {
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  background-color: transparent;
  color: var(--text, #e2e8f0);
  border: 1px solid var(--border-light, #334155);
  border-radius: 8px;
  padding: 0.5rem 2.25rem 0.5rem 0.75rem; /* space for arrow */
  line-height: 1.4;
}
.school-select:focus {
  outline: none;
  border-color: var(--primary, #3b82f6);
  box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.5); /* blue-500 */
}
/* Hide default arrow on IE */
.school-select::-ms-expand { display: none; }
/* Custom arrow icon (using the existing lucide icon element) */
.select-arrow {
  position: absolute;
  right: 0.75rem;
  top: 50%;
  transform: translateY(-50%);
  pointer-events: none;
  opacity: 0.7;
}
.custom-select-container .display:hover .select-arrow { opacity: 1; }

/* Option styling (limited by browser support) */
.school-select option {
  background-color: var(--card, #0f172a); /* fallbacks for dark dropdown */
  color: var(--text, #e2e8f0);
}
.school-select option[disabled] {
  color: var(--text-muted, #64748b);
}
.school-select optgroup {
  background-color: var(--card, #0f172a);
  color: var(--text-secondary, #94a3b8);
}

/* Improve contrast on high-contrast devices */
@media (prefers-contrast: more) {
  .school-select { border-color: var(--border, #1f2937); }
}

/* === Tweaks: refine existing notifications styles (overrides) === */

/* Dropdown: tighter visuals, hidden overflow, subtle border and shadow */
.notifications-dropdown {
  max-height: 70vh;
  overflow: hidden;
  border: 1px solid var(--border-light, #334155);
  box-shadow: 0 10px 30px var(--shadow, rgba(0,0,0,0.25));
}

/* Header: keep visible when scrolling inside the panel */
.notifications-header {
  position: sticky;
  top: 0;
  z-index: 2;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.03));
}

/* Footer: light separation */
.notifications-footer {
  background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.03));
}

/* List: larger viewport-based height and refined scrollbar */
.notifications-list {
  max-height: 50vh;
  scrollbar-width: thin;
  scrollbar-color: rgba(255,255,255,0.25) transparent;
}
.notifications-list::-webkit-scrollbar {
  width: 8px;
}
.notifications-list::-webkit-scrollbar-thumb {
  background: rgba(255,255,255,0.18);
  border-radius: 8px;
}

/* Loading spinner used inside notifications-loading */
.loading-spinner {
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255,255,255,0.2);
  border-top: 2px solid rgba(255,255,255,0.7);
  border-radius: 50%;
  animation: header-spin 1s linear infinite;
}
@keyframes header-spin { to { transform: rotate(360deg); } }

/* Notification item: smoother hover and unread accent */
.notification-item {
  transition: background-color .2s ease, color .2s ease, border-color .2s ease, transform .2s ease;
}
.notification-item:hover {
  background: rgba(255,255,255,0.06);
  transform: translateY(-1px);
}
/* Keep your existing unread styles and add a slim accent bar */
.notification-item.unread::before {
  left: 0;
  width: 3px;
  height: calc(100% - 24px);
  top: 12px;
  background: var(--blue-light, #60a5fa);
  border-radius: 2px;
}

/* Icon circle: subtle background and border for contrast */
.notification-icon {
  background: rgba(255,255,255,0.08);
  border: 1px solid rgba(255,255,255,0.08);
}

/* Typography fallbacks for readability */
.notification-title { color: var(--text, #e2e8f0); }
.notification-message { color: var(--text-secondary, #94a3b8); }
.notification-meta { color: var(--text-muted, #64748b); }

/* Ensure dropdown overlays content properly */
.profile-dropdown,
.notifications-dropdown { z-index: 50; }

/* === End tweaks === */

/* === intl-tel-input: enforce high-contrast dark dropdown === */
.iti--container { z-index: 2147483647 !important; }
.iti--container .iti__country-list {
  background-color: #0b1220 !important; /* deep slate */
  color: #e5e7eb !important;            /* slate-200 */
  border: 1px solid rgba(148,163,184,0.22) !important;
  box-shadow: 0 16px 40px rgba(0,0,0,0.55) !important;
  border-radius: 10px !important;
  max-height: 65vh !important;
  overflow-y: auto !important;
  font-family: inherit !important;
}
.iti--container .iti__country-list .iti__country {
  display: flex !important;
  align-items: center !important;
  gap: 8px !important;
  padding: 10px 12px !important;
  font-size: 14px !important;
  font-weight: 500 !important;
  color: #e5e7eb !important;
  background: transparent !important;
  line-height: 1.35 !important;
  border-bottom: 1px solid rgba(255,255,255,0.06) !important;
}
.iti--container .iti__country-list .iti__country:last-child { border-bottom: none !important; }
.iti--container .iti__flag-box { margin-right: 4px !important; }
.iti--container .iti__flag-box img { opacity: 1 !important; filter: none !important; }
.iti--container .iti__country-name { color: #e5e7eb !important; }
.iti--container .iti__dial-code { color: #9ca3af !important; }
.iti--container .iti__country.iti__highlight,
.iti--container .iti__country:hover,
.iti--container .iti__country[aria-selected="true"] {
  background-color: rgba(99,102,241,0.24) !important; /* indigo-500/24 */
}
.iti--container .iti__country:hover .iti__country-name,
.iti--container .iti__country.iti__highlight .iti__country-name,
.iti--container .iti__country[aria-selected="true"] .iti__country-name { color: #ffffff !important; }
.iti--container .iti__country:hover .iti__dial-code,
.iti--container .iti__country.iti__highlight .iti__dial-code,
.iti--container .iti__country[aria-selected="true"] .iti__dial-code { color: #e5e7eb !important; }
.iti--container .iti__divider { border-color: rgba(148,163,184,0.28) !important; }
.iti--container .iti__search-input {
  background-color: rgba(2,6,23,0.7) !important; /* slate-950/70 */
  color: #e5e7eb !important;
  border: 1px solid rgba(148,163,184,0.28) !important;
}
.iti--container .iti__search-input::placeholder { color: #94a3b8 !important; }
.iti--container .iti__country-list::-webkit-scrollbar { width: 8px; }
.iti--container .iti__country-list::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.22); border-radius: 8px; }
.iti--container .iti__country-list { scrollbar-width: thin; scrollbar-color: rgba(255,255,255,0.22) transparent; }
/* Keyboard focus visibility */
.iti--container .iti__country:focus { outline: 2px solid #60a5fa !important; outline-offset: -2px !important; }