:root {
    --bg: #f8fafc;
    --fg: #0f172a;
    --muted: #64748b;
    --accent: #f97316;
    --card: #ffffff;
    --border: #e2e8f0;
    --brand: #0d9488
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box
}

body {
    font-family: 'DM Sans', sans-serif;
    background: var(--bg);
    color: var(--fg);
    overflow-x: hidden
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: 'Space Grotesk', sans-serif
}

::-webkit-scrollbar {
    width: 6px
}

::-webkit-scrollbar-track {
    background: transparent
}

::-webkit-scrollbar-thumb {
    background: #94a3b8;
    border-radius: 3px
}

/* Landing Animations */
@keyframes float {
    0%, 100% {
        transform: translateY(0) rotate(0deg)
    }
    50% {
        transform: translateY(-20px) rotate(3deg)
    }
}

@keyframes float2 {
    0%, 100% {
        transform: translateY(0) rotate(0deg)
    }
    50% {
        transform: translateY(-15px) rotate(-2deg)
    }
}

@keyframes gradient-shift {
    0% {
        background-position: 0% 50%
    }
    50% {
        background-position: 100% 50%
    }
    100% {
        background-position: 0% 50%
    }
}

@keyframes fade-up {
    from {
        opacity: 0;
        transform: translateY(30px)
    }
    to {
        opacity: 1;
        transform: translateY(0)
    }
}

@keyframes pulse-ring {
    0% {
        transform: scale(.8);
        opacity: 1
    }
    100% {
        transform: scale(2);
        opacity: 0
    }
}

@keyframes slide-in-right {
    from {
        opacity: 0;
        transform: translateX(40px)
    }
    to {
        opacity: 1;
        transform: translateX(0)
    }
}

@keyframes count-up {
    from {
        opacity: 0;
        transform: scale(.5)
    }
    to {
        opacity: 1;
        transform: scale(1)
    }
}

.float-1 {
    animation: float 6s ease-in-out infinite
}

.float-2 {
    animation: float2 5s ease-in-out infinite 1s
}

.float-3 {
    animation: float 7s ease-in-out infinite .5s
}

.gradient-text {
    background: linear-gradient(135deg, #0d9488, #14b8a6, #f97316);
    background-size: 200% 200%;
    animation: gradient-shift 4s ease infinite;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text
}

.fade-up {
    animation: fade-up .6s ease forwards
}

.slide-in {
    animation: slide-in-right .5s ease forwards
}

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all .6s ease
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0)
}

/* Card Hover */
.course-card {
    transition: all .3s ease
}

.course-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, .1)
}

.feature-card {
    transition: all .3s ease
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: var(--brand)
}

/* Button Styles */
.btn-primary {
    background: linear-gradient(135deg, #0d9488, #0f766e);
    color: white;
    padding: 12px 28px;
    border-radius: 12px;
    font-weight: 600;
    transition: all .3s ease;
    border: none;
    cursor: pointer;
    font-family: 'Space Grotesk', sans-serif;
    display: inline-block;
    text-align: center
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(13, 148, 136, .4)
}

.btn-accent {
    background: linear-gradient(135deg, #f97316, #ea580c);
    color: white;
    padding: 12px 28px;
    border-radius: 12px;
    font-weight: 600;
    transition: all .3s ease;
    border: none;
    cursor: pointer;
    font-family: 'Space Grotesk', sans-serif;
    display: inline-block;
    text-align: center
}

.btn-accent:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(249, 115, 22, .4)
}

.btn-outline {
    border: 2px solid var(--brand);
    color: var(--brand);
    padding: 10px 26px;
    border-radius: 12px;
    font-weight: 600;
    transition: all .3s ease;
    background: transparent;
    cursor: pointer;
    font-family: 'Space Grotesk', sans-serif;
    display: inline-block;
    text-align: center
}

.btn-outline:hover {
    background: var(--brand);
    color: white
}

.btn-sm {
    padding: 8px 16px;
    font-size: 13px;
    border-radius: 8px
}

.btn-danger {
    background: #ef4444;
    color: white;
    padding: 8px 16px;
    border-radius: 8px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all .2s;
    display: inline-block;
    text-align: center
}

.btn-danger:hover {
    background: #dc2626
}

/* Admin Sidebar */
.admin-sidebar {
    width: 260px;
    min-height: 100vh;
    background: linear-gradient(180deg, #0C1222 0%, #111827 100%);
    transition: all .3s ease
}

.admin-sidebar .nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 11px 20px;
    color: #94a3b8;
    cursor: pointer;
    transition: all .2s;
    border-radius: 10px;
    margin: 2px 12px;
    font-size: 14px
}

.admin-sidebar .nav-item:hover {
    color: #e2e8f0;
    background: rgba(255, 255, 255, .05)
}

.admin-sidebar .nav-item.active {
    color: #14b8a6;
    background: rgba(20, 184, 166, .1);
    font-weight: 600
}

.admin-sidebar .nav-item.active i {
    color: #14b8a6
}

/* Student Sidebar */
.student-sidebar {
    width: 240px;
    min-height: 100vh;
    background: white;
    border-right: 1px solid var(--border)
}

.student-sidebar .nav-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 16px;
    color: var(--muted);
    cursor: pointer;
    transition: all .2s;
    border-radius: 8px;
    margin: 2px 8px;
    font-size: 14px
}

.student-sidebar .nav-item:hover {
    color: var(--fg);
    background: #f1f5f9
}

.student-sidebar .nav-item.active {
    color: var(--brand);
    background: #f0fdfa;
    font-weight: 600
}

/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, .5);
    backdrop-filter: blur(4px);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: all .3s
}

.modal-overlay.show {
    opacity: 1;
    pointer-events: all
}

.modal-content {
    background: white;
    border-radius: 16px;
    max-width: 600px;
    width: 90%;
    max-height: 85vh;
    overflow-y: auto;
    transform: scale(.9);
    transition: all .3s
}

.modal-overlay.show .modal-content {
    transform: scale(1)
}

/* Toast */
.toast {
    padding: 14px 20px;
    border-radius: 12px;
    color: white;
    font-size: 14px;
    font-weight: 500;
    animation: slide-in-right .4s ease;
    box-shadow: 0 10px 40px rgba(0, 0, 0, .15);
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 280px
}

.toast.success {
    background: linear-gradient(135deg, #059669, #10b981)
}

.toast.error {
    background: linear-gradient(135deg, #dc2626, #ef4444)
}

.toast.info {
    background: linear-gradient(135deg, #0d9488, #14b8a6)
}

/* Video Player */
.video-player {
    aspect-ratio: 16/9;
    background: #0f172a;
    border-radius: 12px;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center
}

.video-player .play-btn {
    width: 70px;
    height: 70px;
    background: rgba(255, 255, 255, .15);
    backdrop-filter: blur(10px);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all .3s;
    border: 2px solid rgba(255, 255, 255, .3)
}

.video-player .play-btn:hover {
    background: rgba(255, 255, 255, .25);
    transform: scale(1.1)
}

.video-progress {
    height: 4px;
    background: rgba(255, 255, 255, .2);
    border-radius: 2px;
    cursor: pointer;
    position: relative
}

.video-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #14b8a6, #f97316);
    border-radius: 2px;
    transition: width .1s linear
}

/* Stats Card */
.stat-card {
    background: white;
    border-radius: 16px;
    padding: 24px;
    border: 1px solid var(--border);
    transition: all .3s
}

.stat-card:hover {
    border-color: #14b8a6;
    box-shadow: 0 8px 30px rgba(13, 148, 136, .08)
}

/* Input */
.form-input {
    width: 100%;
    padding: 10px 14px;
    border: 2px solid var(--border);
    border-radius: 10px;
    font-size: 14px;
    transition: all .2s;
    font-family: 'DM Sans', sans-serif;
    outline: none
}

.form-input:focus {
    border-color: var(--brand);
    box-shadow: 0 0 0 3px rgba(13, 148, 136, .1)
}

.form-label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--muted);
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: .5px
}

select.form-input {
    cursor: pointer;
    appearance: none;
    background: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%2364748b' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10z'/%3E%3C/svg%3E") no-repeat right 12px center white
}

textarea.form-input {
    resize: vertical;
    min-height: 80px
}

/* Table */
.data-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0
}

.data-table th {
    background: #f8fafc;
    padding: 12px 16px;
    text-align: left;
    font-size: 12px;
    font-weight: 700;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: .5px;
    border-bottom: 2px solid var(--border)
}

.data-table td {
    padding: 12px 16px;
    border-bottom: 1px solid var(--border);
    font-size: 14px
}

.data-table tr:hover td {
    background: #f8fafc
}

.badge {
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    display: inline-block
}

.badge-green {
    background: #dcfce7;
    color: #166534
}

.badge-yellow {
    background: #fef3c7;
    color: #92400e
}

.badge-red {
    background: #fee2e2;
    color: #991b1b
}

.badge-blue {
    background: #dbeafe;
    color: #1e40af
}

.badge-teal {
    background: #ccfbf1;
    color: #0f766e
}

/* Offer Letter */
.offer-letter {
    background: white;
    border: 3px solid #0f766e;
    padding: 48px;
    max-width: 700px;
    margin: auto;
    font-family: 'DM Sans', serif
}

.offer-letter .header-line {
    height: 3px;
    background: linear-gradient(90deg, #0d9488, #f97316);
    margin: 16px 0 24px
}

/* Particle Canvas */
#particles {
    position: absolute;
    inset: 0;
    pointer-events: none
}

/* Responsive */
@media(max-width:768px) {
    .admin-sidebar,
    .student-sidebar {
        display: none !important
    }

    .admin-mobile-nav,
    .student-mobile-nav {
        display: flex !important
    }
}

/* Animated Checkmark Tick */
.checkmark-circle {
    width: 80px;
    height: 80px;
    position: relative;
    display: inline-block;
    vertical-align: top;
    margin: 0 auto 20px;
}
.checkmark-circle .background {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: #10b981;
    position: absolute;
    animation: pulse-checkmark 1.5s ease-out infinite;
}
.checkmark-circle .checkmark {
    border-radius: 5px;
}
.checkmark-circle .checkmark.draw:after {
    animation-duration: 800ms;
    animation-timing-function: ease;
    animation-name: checkmark-draw;
    transform: scaleX(-1) rotate(135deg);
}
.checkmark-circle .checkmark:after {
    opacity: 1;
    height: 40px;
    width: 20px;
    transform-origin: left top;
    border-right: 5px solid white;
    border-top: 5px solid white;
    content: '';
    left: 22px;
    top: 42px;
    position: absolute;
}
@keyframes checkmark-draw {
    0% {
        height: 0;
        width: 0;
        opacity: 1;
    }
    20% {
        height: 0;
        width: 20px;
        opacity: 1;
    }
    40% {
        height: 40px;
        width: 20px;
        opacity: 1;
    }
    100% {
        height: 40px;
        width: 20px;
        opacity: 1;
    }
}
@keyframes pulse-checkmark {
    0% {
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4);
    }
    70% {
        box-shadow: 0 0 0 15px rgba(16, 185, 129, 0);
    }
    100% {
        box-shadow: 0 0 0 0 rgba(16, 185, 129, 0);
    }
}