:root {
    --gdg-blue: #4285F4;
    --gdg-red: #EA4335;
    --gdg-yellow: #FBBC04;
    --gdg-green: #34A853;
    --gdg-light-blue: #00D1FF;

    --bg-dark: #0f1115;
    --bg-card: #1c1f26;
    --bg-alt: #16191f;
    --text-main: #f0f2f5;
    --text-muted: #9ba1b0;
    --border: #2e3541;

    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-dark);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

h1,
h2,
h3,
.logo-text {
    font-family: 'Outfit', sans-serif;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* Header */
.header {
    background: rgba(15, 17, 21, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.header-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 500;
}

.gdg-logo {
    height: 32px;
    width: auto;
}

.nav {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
}

.nav-link:hover {
    color: var(--gdg-light-blue);
}

.cta-button {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    text-decoration: none;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    font-family: inherit;
    font-size: 1rem;
}

.cta-button.primary {
    background: linear-gradient(135deg, var(--gdg-blue), var(--gdg-light-blue));
    color: white;
}

.cta-button.primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 20px rgba(0, 209, 255, 0.3);
}

.cta-button.secondary {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-main);
}

.cta-button.secondary:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--text-muted);
}

/* Hero */
.hero {
    padding: 160px 0 100px;
    position: relative;
    overflow: hidden;
}

.hero-bg-blur {
    position: absolute;
    top: -100px;
    right: -100px;
    width: 400px;
    height: 400px;
    background: var(--gdg-blue);
    filter: blur(120px);
    opacity: 0.15;
    z-index: -1;
}

.hero-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 4rem;
}

.hero-content {
    flex: 1;
}

.hero-image-container {
    flex: 1;
    max-width: 500px;
    position: relative;
    z-index: 1;
}

.hero-image {
    width: 100%;
    height: auto;
    border-radius: 24px;
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5),
        0 0 30px rgba(66, 133, 244, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transform: perspective(1000px) rotateY(-5deg);
    transition: var(--transition);
}

.hero-image:hover {
    transform: perspective(1000px) rotateY(0deg) scale(1.02);
}

.hero-title {
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    font-weight: 800;
}

.highlight {
    background: linear-gradient(135deg, var(--gdg-light-blue), var(--gdg-blue));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-muted);
    max-width: 600px;
    margin-bottom: 2.5rem;
}

.hero-actions {
    display: flex;
    gap: 1rem;
}

/* Sections */
.section {
    padding: 100px 0;
}

.bg-alt {
    background-color: var(--bg-alt);
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    text-align: center;
}

.section-intro {
    text-align: center;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto 3rem;
    font-size: 1.1rem;
}

/* Grid */
.grid {
    display: grid;
    gap: 2rem;
}

.categories-grid {
    grid-template-columns: repeat(2, 1fr);
}

.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 2.5rem;
    transition: var(--transition);
}

.card:hover {
    border-color: var(--gdg-blue);
    transform: translateY(-5px);
}

.card-icon {
    font-size: 3rem;
    margin-bottom: 1.5rem;
}

.card-title {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.card-focus {
    color: var(--gdg-light-blue);
    font-weight: 600;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 1rem;
}

.card-text {
    color: var(--text-muted);
    margin-bottom: 1.5rem;
}

.tech-tag {
    display: inline-block;
    padding: 0.4rem 1rem;
    background: rgba(66, 133, 244, 0.1);
    border: 1px solid rgba(66, 133, 244, 0.2);
    border-radius: 20px;
    color: var(--gdg-blue);
    font-size: 0.85rem;
    font-weight: 600;
}

.requirements {
    margin-top: 3rem;
    text-align: center;
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: 12px;
}

/* Judging */
.judging-grid {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.judging-item {
    text-align: center;
}

.judging-percent {
    font-size: 3rem;
    font-weight: 800;
    color: var(--gdg-light-blue);
    margin-bottom: 1rem;
}

.judging-title {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.judging-flow {
    margin-top: 5rem;
    padding: 3rem;
    background: rgba(255, 255, 255, 0.02);
    border-radius: 20px;
    border: 1px solid var(--border);
}

.judging-flow-title {
    font-size: 1.75rem;
    margin-bottom: 2.5rem;
    text-align: center;
}

.flow-container {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    max-width: 800px;
    margin: 0 auto;
}

.flow-step {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    background: var(--bg-card);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border);
}

.flow-number {
    width: 40px;
    height: 40px;
    background: var(--gdg-blue);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    flex-shrink: 0;
}

.flow-desc strong {
    display: block;
    margin-bottom: 0.25rem;
    color: var(--gdg-light-blue);
}

.flow-desc p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.prohibited-container {
    margin-top: 5rem;
    background: rgba(234, 67, 53, 0.05);
    border: 1px solid rgba(234, 67, 53, 0.1);
    border-radius: 20px;
    padding: 3rem;
}

.prohibited-title {
    color: var(--gdg-red);
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    text-align: center;
}

.prohibited-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
    list-style: none;
}

.prohibited-list li {
    padding-left: 1.5rem;
    position: relative;
    color: var(--text-muted);
}

.prohibited-list li::before {
    content: "✕";
    position: absolute;
    left: 0;
    color: var(--gdg-red);
    font-weight: bold;
}

/* Setup */
.setup-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
}

.setup-tab {
    padding: 0.75rem 2rem;
    border: 1px solid var(--border);
    border-radius: 30px;
    cursor: pointer;
    transition: var(--transition);
}

.setup-tab.active {
    background: var(--gdg-blue);
    border-color: var(--gdg-blue);
    color: white;
}

.setup-content {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 3rem;
}

.setup-steps {
    margin: 1.5rem 0;
    padding-left: 1.5rem;
}

.setup-steps li {
    margin-bottom: 1rem;
}

.link {
    color: var(--gdg-light-blue);
    text-decoration: none;
}

.link:hover {
    text-decoration: underline;
}

.alert {
    padding: 1rem 1.5rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
}

.alert.note {
    background: rgba(251, 188, 4, 0.1);
    border-left: 4px solid var(--gdg-yellow);
    color: var(--gdg-yellow);
}

.code-block {
    background: #000;
    padding: 1.5rem;
    border-radius: 12px;
    overflow-x: auto;
    margin-top: 1rem;
}

.code-block code {
    font-family: 'Monaco', 'Consolas', monospace;
    font-size: 0.9rem;
    color: #e0e0e0;
}

.hidden {
    display: none;
}

/* Form */
.form {
    max-width: 600px;
    margin: 0 auto;
    background: var(--bg-card);
    padding: 3rem;
    border-radius: 20px;
    border: 1px solid var(--border);
}

.form-group {
    margin-bottom: 1.5rem;
}

.label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-muted);
}

.input {
    width: 100%;
    padding: 0.85rem 1rem;
    background: #0f1115;
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-main);
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.input:focus {
    outline: none;
    border-color: var(--gdg-blue);
    box-shadow: 0 0 0 4px rgba(66, 133, 244, 0.1);
}

.full-width {
    width: 100%;
}

.form-status {
    margin-top: 1.5rem;
    text-align: center;
    border-radius: 8px;
    font-weight: 500;
}

.form-status.success {
    padding: 1rem;
    background: rgba(52, 168, 83, 0.1);
    color: var(--gdg-green);
}

.form-status.error {
    padding: 1rem;
    background: rgba(234, 67, 53, 0.1);
    color: var(--gdg-red);
}

/* Footer */
.footer {
    padding: 4rem 0;
    border-top: 1px solid var(--border);
    text-align: center;
    color: var(--text-muted);
}

/* Animations */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.reveal.in-view {
    opacity: 1;
    transform: translateY(0);
}

.card.reveal {
    transition-delay: 0.1s;
}

.category-card:nth-child(2).reveal {
    transition-delay: 0.2s;
}

@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .header-container {
        flex-direction: column;
        height: auto;
        padding: 1rem;
    }

    .nav {
        display: none;
        /* Mobile menu needed */
    }

    .hero-actions {
        flex-direction: column;
    }

    .container {
        padding: 0 1.5rem;
    }

    .section {
        padding: 60px 0;
    }

    .header-container {
        height: 70px;
    }

    /* Mobile Nav */
    .menu-toggle {
        display: flex;
        flex-direction: column;
        gap: 6px;
        cursor: pointer;
        z-index: 1001;
    }

    .bar {
        width: 28px;
        height: 3px;
        background-color: var(--text-main);
        border-radius: 2px;
        transition: var(--transition);
    }

    .nav {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        height: 100vh;
        background: var(--bg-dark);
        flex-direction: column;
        justify-content: center;
        gap: 2.5rem;
        padding: 4rem 2rem;
        transition: var(--transition);
        box-shadow: -10px 0 30px rgba(0, 0, 0, 0.5);
        border-left: 1px solid var(--border);
        z-index: 1000;
    }

    .nav.active {
        right: 0;
    }

    .nav-cta {
        width: 100%;
        text-align: center;
    }

    #mobile-menu.active .bar:nth-child(1) {
        transform: translateY(9px) rotate(45deg);
    }

    #mobile-menu.active .bar:nth-child(2) {
        opacity: 0;
    }

    #mobile-menu.active .bar:nth-child(3) {
        transform: translateY(-9px) rotate(-45deg);
    }

    /* Hero */
    .hero {
        padding: 120px 0 60px;
        text-align: center;
    }

    .hero-container {
        flex-direction: column;
        gap: 3rem;
    }

    .hero-title {
        font-size: 2.75rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
        margin: 0 auto 2rem;
    }

    .hero-actions {
        flex-direction: column;
        gap: 0.75rem;
    }

    .hero-image-container {
        max-width: 100%;
        order: -1;
    }

    .hero-image {
        transform: none;
    }

    .hero-image:hover {
        transform: scale(1.02);
    }

    /* Sections */
    .section-title {
        font-size: 2rem;
    }

    .card {
        padding: 1.5rem;
    }

    .judging-percent {
        font-size: 2.5rem;
    }

    .judging-flow {
        padding: 1.5rem;
        margin-top: 3rem;
    }

    .prohibited-container {
        padding: 1.5rem;
        margin-top: 3rem;
    }

    .prohibited-list {
        grid-template-columns: 1fr;
    }

    .setup-tab {
        padding: 0.6rem 1.2rem;
        font-size: 0.9rem;
    }

    .setup-content {
        padding: 1.5rem;
    }

    .form {
        padding: 1.5rem;
    }

    .categories-grid {
        grid-template-columns: 1fr;
    }
}