/* Base Styles & Variables */

:root {
    --primary: #00f0ff;
    --primary-dark: #00a8b3;
    --secondary: #ff00e5;
    --secondary-dark: #b300a1;
    --accent: #ffee00;
    --bg-dark: #0a0a0f;
    --bg-darker: #050508;
    --bg-card: rgba(20, 20, 35, 0.8);
    --text: #ffffff;
    --text-muted: #8888aa;
    --success: #00ff88;
    --warning: #ffaa00;
    --danger: #ff4466;
    --gradient-1: linear-gradient(135deg, var(--primary), var(--secondary));
    --gradient-2: linear-gradient(135deg, var(--secondary), var(--accent));
    --glow-primary: 0 0 20px rgba(0, 240, 255, 0.5);
    --glow-secondary: 0 0 20px rgba(255, 0, 229, 0.5);
}

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

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: 'Rajdhani', sans-serif;
    background: var(--bg-dark);
    color: var(--text);
    line-height: 1.6;
}

/* Particles Background */

.particles {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    background: var(--primary);
    border-radius: 50%;
    opacity: 0.5;
    animation: float 8s infinite ease-in-out;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) translateX(0);
        opacity: 0.5;
    }
    50% {
        transform: translateY(-100px) translateX(50px);
        opacity: 0.2;
    }
}

/* Back to Vault Button */

.back-to-vault {
    position: fixed;
    top: 1.5rem;
    left: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    background: rgba(20, 20, 35, 0.8);
    border: 1px solid rgba(0, 240, 255, 0.3);
    border-radius: 30px;
    color: var(--text-muted);
    text-decoration: none;
    font-family: 'Rajdhani', sans-serif;
    font-size: 0.95rem;
    font-weight: 500;
    z-index: 100;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.back-to-vault:hover {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: var(--glow-primary);
    transform: translateX(-3px);
}

.back-arrow {
    font-size: 1.2rem;
    transition: transform 0.3s ease;
}

.back-to-vault:hover .back-arrow {
    transform: translateX(-3px);
}

.back-text {
    letter-spacing: 0.05em;
}

/* Landing Page Styles */

.landing-page {
    background:
        radial-gradient(ellipse at 50% 0%, rgba(0, 240, 255, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 80%, rgba(255, 0, 229, 0.1) 0%, transparent 40%),
        var(--bg-darker);
}

.landing-container {
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

/* Logo */
.landing-header {
    text-align: center;
    margin-bottom: 3rem;
}

.logo-container {
    position: relative;
    display: inline-block;
}

.logo-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 300px;
    height: 100px;
    background: var(--gradient-1);
    filter: blur(60px);
    opacity: 0.5;
    animation: pulse-glow 3s infinite ease-in-out;
}

@keyframes pulse-glow {
    0%, 100% { opacity: 0.3; transform: translate(-50%, -50%) scale(1); }
    50% { opacity: 0.6; transform: translate(-50%, -50%) scale(1.1); }
}

.logo {
    font-family: 'Orbitron', sans-serif;
    font-size: 4rem;
    font-weight: 900;
    letter-spacing: 0.1em;
    position: relative;
}

.logo .beat {
    color: var(--primary);
    text-shadow: var(--glow-primary);
}

.logo .burst {
    color: var(--secondary);
    text-shadow: var(--glow-secondary);
}

.tagline {
    font-size: 1.3rem;
    color: var(--text-muted);
    margin-top: 1rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
}

/* Features */
.features {
    display: flex;
    gap: 2rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
    justify-content: center;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    width: 220px;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-10px);
    border-color: var(--primary);
    box-shadow: var(--glow-primary);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-family: 'Orbitron', sans-serif;
    font-size: 1rem;
    margin-bottom: 0.5rem;
    color: var(--primary);
}

.feature-card p {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* Start Button */
.start-button {
    position: relative;
    display: inline-block;
    padding: 1.2rem 3rem;
    font-family: 'Orbitron', sans-serif;
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--bg-dark);
    background: var(--gradient-1);
    border: none;
    border-radius: 50px;
    cursor: pointer;
    text-decoration: none;
    overflow: hidden;
    transition: all 0.3s ease;
}

.start-button:hover {
    transform: scale(1.05);
    box-shadow: var(--glow-primary), var(--glow-secondary);
}

.button-glow {
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
    animation: shine 2s infinite;
}

@keyframes shine {
    0% { left: -100%; }
    50%, 100% { left: 100%; }
}

/* Pulse Bars Footer */
.landing-footer {
    position: absolute;
    bottom: 2rem;
}

.pulse-bars {
    display: flex;
    align-items: flex-end;
    gap: 4px;
    height: 40px;
}

.pulse-bars span {
    width: 6px;
    background: var(--gradient-1);
    border-radius: 3px;
    animation: pulse-bar 1s infinite ease-in-out;
}

.pulse-bars span:nth-child(1) { animation-delay: 0s; height: 20px; }
.pulse-bars span:nth-child(2) { animation-delay: 0.1s; height: 30px; }
.pulse-bars span:nth-child(3) { animation-delay: 0.2s; height: 40px; }
.pulse-bars span:nth-child(4) { animation-delay: 0.3s; height: 25px; }
.pulse-bars span:nth-child(5) { animation-delay: 0.4s; height: 35px; }
.pulse-bars span:nth-child(6) { animation-delay: 0.5s; height: 20px; }
.pulse-bars span:nth-child(7) { animation-delay: 0.6s; height: 40px; }
.pulse-bars span:nth-child(8) { animation-delay: 0.7s; height: 30px; }
.pulse-bars span:nth-child(9) { animation-delay: 0.8s; height: 25px; }
.pulse-bars span:nth-child(10) { animation-delay: 0.9s; height: 35px; }

@keyframes pulse-bar {
    0%, 100% { transform: scaleY(0.5); opacity: 0.5; }
    50% { transform: scaleY(1); opacity: 1; }
}

/* Shared Components */
.screen {
    display: none;
    width: 100%;
    height: 100vh;
    position: relative;
}

.screen.active {
    display: flex;
    flex-direction: column;
}

.back-button {
    position: absolute;
    top: 1.5rem;
    left: 1.5rem;
    color: var(--text-muted);
    text-decoration: none;
    font-size: 1rem;
    transition: color 0.3s ease;
    z-index: 10;
}

.back-button:hover {
    color: var(--primary);
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(5, 5, 8, 0.95);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.loading-overlay.active {
    display: flex;
}

.loader {
    text-align: center;
}

.loader-ring {
    width: 80px;
    height: 80px;
    border: 4px solid rgba(0, 240, 255, 0.2);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loader-text {
    font-family: 'Orbitron', sans-serif;
    color: var(--primary);
    font-size: 1.1rem;
}

/* Responsive */

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

    .tagline {
        font-size: 1rem;
    }

    .features {
        flex-direction: column;
        align-items: center;
    }

    .feature-card {
        width: 100%;
        max-width: 280px;
    }

    .start-button {
        padding: 1rem 2rem;
        font-size: 1rem;
    }
}

/* Scrollable Landing */

.landing-container.scrollable {
    min-height: 100vh;
    height: auto;
    overflow-y: auto;
    overflow-x: hidden;
    padding-bottom: 6rem;
}

html:has(.scrollable), body:has(.scrollable) {
    overflow: auto;
    height: auto;
}

/* Section Titles */

.section-title {
    font-family: 'Orbitron', sans-serif;
    font-size: 1.8rem;
    text-align: center;
    margin-bottom: 0.5rem;
    background: var(--gradient-1);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-subtitle {
    text-align: center;
    color: var(--text-muted);
    margin-bottom: 2rem;
    font-size: 1rem;
}

/* Interactive Beat Pad */

.beat-pad-section {
    margin: 3rem 0;
    padding: 2rem;
    background: var(--bg-card);
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    max-width: 700px;
    width: 100%;
}

.beat-pad-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.beat-visualizer {
    width: 100%;
    height: 120px;
    background: rgba(0, 0, 0, 0.3);
    border-radius: 12px;
    border: 1px solid rgba(0, 240, 255, 0.2);
}

.beat-pads {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.75rem;
    width: 100%;
    max-width: 500px;
}

.beat-pad {
    aspect-ratio: 1;
    background: linear-gradient(145deg, rgba(30, 30, 50, 0.9), rgba(20, 20, 35, 0.9));
    border: 2px solid rgba(0, 240, 255, 0.3);
    border-radius: 12px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.15s ease;
    user-select: none;
    position: relative;
    overflow: hidden;
}

.beat-pad::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-1);
    opacity: 0;
    transition: opacity 0.15s ease;
}

.beat-pad:hover {
    border-color: var(--primary);
    transform: scale(1.02);
}

.beat-pad:active,
.beat-pad.active {
    transform: scale(0.95);
    border-color: var(--primary);
    box-shadow: var(--glow-primary), inset 0 0 30px rgba(0, 240, 255, 0.3);
}

.beat-pad.active::before {
    opacity: 0.3;
}

.pad-key {
    font-family: 'Orbitron', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    position: relative;
    z-index: 1;
}

.pad-name {
    font-size: 0.7rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-top: 0.25rem;
    position: relative;
    z-index: 1;
}

/* How to Play Section */

.how-to-play {
    margin: 3rem 0;
    max-width: 800px;
    width: 100%;
}

.steps {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.step {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    padding: 1.5rem;
    background: var(--bg-card);
    border-radius: 16px;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s ease;
}

.step:hover {
    border-color: var(--primary);
    transform: translateX(10px);
}

.step-number {
    width: 50px;
    height: 50px;
    min-width: 50px;
    background: var(--gradient-1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Orbitron', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--bg-dark);
}

.step-content h3 {
    font-family: 'Orbitron', sans-serif;
    font-size: 1.1rem;
    color: var(--primary);
    margin-bottom: 0.5rem;
}

.step-content p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.5;
}

/* Controls Info */
.controls-info {
    background: var(--bg-card);
    border-radius: 16px;
    padding: 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.controls-info h3 {
    font-family: 'Orbitron', sans-serif;
    font-size: 1rem;
    color: var(--secondary);
    text-align: center;
    margin-bottom: 1rem;
}

.key-grid {
    display: flex;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.key-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.key {
    width: 50px;
    height: 50px;
    background: linear-gradient(145deg, rgba(40, 40, 60, 0.9), rgba(20, 20, 35, 0.9));
    border: 2px solid var(--primary);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Orbitron', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    color: var(--primary);
    box-shadow: 0 4px 0 rgba(0, 0, 0, 0.3);
}

.key-label {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Scoring Section */

.scoring-section {
    margin: 3rem 0;
    max-width: 700px;
    width: 100%;
}

.score-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
}

.score-card {
    background: var(--bg-card);
    border-radius: 12px;
    padding: 1.25rem 0.75rem;
    text-align: center;
    border: 2px solid transparent;
    transition: all 0.3s ease;
}

.score-card:hover {
    transform: translateY(-5px);
}

.score-card.perfect {
    border-color: var(--success);
}

.score-card.perfect .score-label,
.score-card.perfect .score-points {
    color: var(--success);
}

.score-card.great {
    border-color: var(--primary);
}

.score-card.great .score-label,
.score-card.great .score-points {
    color: var(--primary);
}

.score-card.good {
    border-color: var(--warning);
}

.score-card.good .score-label,
.score-card.good .score-points {
    color: var(--warning);
}

.score-card.miss {
    border-color: var(--danger);
}

.score-card.miss .score-label,
.score-card.miss .score-points {
    color: var(--danger);
}

.score-label {
    font-family: 'Orbitron', sans-serif;
    font-size: 0.85rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.score-points {
    font-family: 'Orbitron', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
}

.score-timing {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Responsive - Extended */

@media (max-width: 768px) {
    .beat-pads {
        grid-template-columns: repeat(4, 1fr);
        gap: 0.5rem;
    }

    .pad-key {
        font-size: 1.2rem;
    }

    .pad-name {
        font-size: 0.6rem;
    }

    .step {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .key-grid {
        gap: 0.75rem;
    }

    .key {
        width: 40px;
        height: 40px;
        font-size: 0.85rem;
    }

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

    .section-title {
        font-size: 1.4rem;
    }
}