/* MultiVoice - Modern & Responsive Styling */
@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&family=Poppins:wght@400;500;600;700&display=swap');

:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary: #ec4899;
    --accent: #f59e0b;
    --success: #10b981;
    --danger: #ef4444;
    --bg-main: #f8fafc;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --glass-bg: rgba(255, 255, 255, 0.9);
    --glass-border: rgba(255, 255, 255, 0.5);
    --card-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.05);
    --hover-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: 'Plus Jakarta Sans', sans-serif;
    background-color: var(--bg-main);
    background-image: 
        radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.1) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(236, 72, 153, 0.1) 0px, transparent 50%);
    min-height: 100vh;
    color: var(--text-main);
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: clamp(1rem, 5vw, 2rem);
}

header {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    padding: 1.25rem 2rem;
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    box-shadow: var(--card-shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    position: sticky;
    top: 1rem;
    z-index: 100;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.025em;
}

.logo p {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-weight: 600;
}

main {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    padding: 2.5rem;
    border-radius: 32px;
    border: 1px solid var(--glass-border);
    box-shadow: var(--card-shadow);
    margin-bottom: 3rem;
}

.language-section h2 {
    text-align: center;
    font-size: 1.875rem;
    font-weight: 800;
    margin-bottom: 2rem;
}

.language-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
}

.language-card {
    background: white;
    padding: 2.5rem 2rem;
    border-radius: 24px;
    text-align: center;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    border: 2px solid transparent;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.language-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--hover-shadow);
    border-color: var(--primary-light);
}

.language-card .flag {
    font-size: 3.5rem;
    margin-bottom: 1rem;
}

.language-card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.btn-primary, .btn-success, .btn-secondary, .btn-danger, .btn-voice {
    padding: 0.8rem 1.5rem;
    border-radius: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
    font-family: inherit;
    font-size: 0.95rem;
}

.btn-primary { background: var(--primary); color: white; box-shadow: 0 4px 10px rgba(99, 102, 241, 0.3); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 15px rgba(99, 102, 241, 0.4); }

.btn-success { background: var(--success); color: white; }
.btn-secondary { background: #e2e8f0; color: var(--text-main); }
.btn-danger { background: var(--danger); color: white; }
.btn-voice { background: var(--secondary); color: white; }

.voice-test-card {
    background: white;
    padding: 2rem;
    border-radius: 24px;
    border: 1px solid #e2e8f0;
    margin-bottom: 2rem;
    text-align: center;
}

/* Learning Area */
.learning-header { text-align: center; margin-bottom: 2rem; }
.progress-bar { background: #e2e8f0; height: 12px; border-radius: 99px; overflow: hidden; margin: 1rem 0; }
.progress-fill { background: linear-gradient(90deg, var(--primary), var(--secondary)); height: 100%; width: 0%; transition: width 0.5s; }

.lesson-container { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; }
.vocabulary-list { display: flex; flex-direction: column; gap: 1rem; }
.vocab-item { background: white; padding: 1.5rem; border-radius: 16px; border: 1px solid #f1f5f9; box-shadow: 0 2px 4px rgba(0,0,0,0.02); }
.vocab-word { font-size: 1.4rem; font-weight: 800; color: var(--primary); }

.ai-call-interface {
    background: #0f172a;
    border-radius: 32px;
    padding: 3rem 1.5rem;
    color: white;
    text-align: center;
    position: relative;
    min-height: 550px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.ai-avatar {
    width: 140px;
    height: 140px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    border-radius: 50%;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
    position: relative;
    box-shadow: 0 0 40px rgba(99, 102, 241, 0.4);
}

.pulse-ring {
    position: absolute;
    width: 100%; height: 100%; border-radius: 50%; border: 2px solid var(--primary);
    animation: ring-pulse 2s infinite; opacity: 0;
}
.delay-1 { animation-delay: 0.5s; }
.delay-2 { animation-delay: 1s; }

@keyframes ring-pulse {
    0% { transform: scale(1); opacity: 0.8; }
    100% { transform: scale(3); opacity: 0; }
}

.call-transcription {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 20px;
    padding: 1.5rem;
    margin: 1.5rem 0;
    height: 150px;
    overflow-y: auto;
    text-align: left;
    font-size: 0.95rem;
}

.trans-msg.ai { color: var(--primary-light); font-weight: 700; }
.trans-msg.user { color: #fff; }

.btn-call-end {
    background: var(--danger);
    color: white;
    padding: 1.25rem;
    border-radius: 99px;
    width: 100%;
    font-size: 1.2rem;
    font-weight: 800;
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
}

@media (max-width: 768px) {
    main { padding: 1.5rem; border-radius: 24px; }
    .lesson-container { grid-template-columns: 1fr; }
    .language-grid { grid-template-columns: 1fr 1fr; gap: 0.75rem; }
    .ai-call-interface { position: fixed; top: 0; left: 0; width: 100%; height: 100vh; z-index: 9999; border-radius: 0; }
    .container { padding: 0.5rem; }
}

@media (max-width: 480px) {
    .language-grid { grid-template-columns: 1fr; }
}

.pulse { animation: simple-pulse 2s infinite; }
@keyframes simple-pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

.meter-fill { height: 100%; background: var(--success); transition: width 0.1s; }
.mic-meter-call { background: rgba(255,255,255,0.1); height: 8px; border-radius: 4px; overflow: hidden; margin-bottom: 1rem; }

.ai-feedback-card {
    background: #fff;
    border-left: 5px solid var(--accent);
    padding: 1rem;
    border-radius: 12px;
    margin-bottom: 1rem;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}