:root {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --border-color: rgba(255, 255, 255, 0.1);
    --error-color: #ef4444;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* App Container */
.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
    width: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* Header */
.app-header {
    display: flex;
    align-items: center;
    margin-bottom: 2rem;
    gap: 1rem;
}

.app-logo {
    font-size: 2rem;
    color: var(--accent-color);
}

.app-title {
    font-size: 1.5rem;
    font-weight: 600;
    letter-spacing: -0.025em;
    background: linear-gradient(to right, #60a5fa, #a78bfa);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Main Translation Area */
.translator-card {
    background-color: var(--bg-secondary);
    border-radius: 1rem;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 8px 10px -6px rgba(0, 0, 0, 0.2);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    position: relative;
}

/* Controls */
.controls-bar {
    display: flex;
    align-items: center;
    padding: 1rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    background-color: rgba(30, 41, 59, 0.8);
    backdrop-filter: blur(8px);
}

.language-selector {
    flex: 1;
    display: flex;
    justify-content: center;
}

select {
    background-color: transparent;
    color: var(--text-primary);
    border: none;
    font-size: 1rem;
    font-family: 'Inter', sans-serif;
    font-weight: 500;
    padding: 0.5rem 2rem 0.5rem 1rem;
    cursor: pointer;
    appearance: none;
    outline: none;
    transition: color 0.2s;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2394a3b8'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1.2rem;
}

select:hover {
    color: var(--accent-color);
}

select option {
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
}

.swap-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 50%;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    justify-content: center;
}

.swap-btn:hover {
    color: var(--text-primary);
    background-color: var(--bg-tertiary);
    transform: rotate(180deg);
}

/* Text Areas */
.text-areas-container {
    display: flex;
    flex-direction: column;
}

@media (min-width: 768px) {
    .text-areas-container {
        flex-direction: row;
    }
}

.text-area-wrapper {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 250px;
    position: relative;
}

.source-area {
    border-bottom: 1px solid var(--border-color);
}

@media (min-width: 768px) {
    .source-area {
        border-bottom: none;
        border-right: 1px solid var(--border-color);
    }
}

textarea {
    width: 100%;
    height: 100%;
    min-height: 250px;
    background-color: transparent;
    border: none;
    color: var(--text-primary);
    font-size: 1.2rem;
    font-family: 'Inter', sans-serif;
    padding: 1.5rem;
    resize: none;
    outline: none;
    line-height: 1.5;
}

textarea::placeholder {
    color: var(--text-secondary);
    font-weight: 300;
}

.target-area {
    background-color: rgba(15, 23, 42, 0.3);
}

.translation-result {
    padding: 1.5rem;
    font-size: 1.2rem;
    line-height: 1.5;
    color: var(--text-primary);
    white-space: pre-wrap;
    word-break: break-word;
    height: 100%;
}

.placeholder-text {
    color: var(--text-secondary);
    font-weight: 300;
}

/* Actions Footer */
.actions-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--border-color);
    background-color: var(--bg-secondary);
}

.char-count {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.char-count.error {
    color: var(--error-color);
}

.btn-primary {
    background-color: var(--accent-color);
    color: white;
    border: none;
    padding: 0.75rem 2rem;
    border-radius: 0.5rem;
    font-size: 1rem;
    font-weight: 500;
    font-family: 'Inter', sans-serif;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: 0 4px 6px -1px rgba(59, 130, 246, 0.4);
}

.btn-primary:hover:not(:disabled) {
    background-color: var(--accent-hover);
    transform: translateY(-1px);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(1px);
}

.btn-primary:disabled {
    background-color: var(--bg-tertiary);
    color: var(--text-secondary);
    cursor: not-allowed;
    box-shadow: none;
}

/* Loading Spinner */
.spinner {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

/* Error Message */
.error-message {
    color: var(--error-color);
    padding: 1rem 1.5rem;
    background-color: rgba(239, 68, 68, 0.1);
    border-bottom: 1px solid rgba(239, 68, 68, 0.2);
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Skeleton Loading */
.skeleton-text {
    height: 1.2rem;
    background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--bg-secondary) 50%, var(--bg-tertiary) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: 0.25rem;
    margin-bottom: 0.5rem;
}

.skeleton-text.w-3-4 { width: 75%; }
.skeleton-text.w-1-2 { width: 50%; }

@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

/* Footer */
.app-footer {
    margin-top: auto;
    text-align: center;
    padding: 2rem 0;
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.copy-btn {
    position: absolute;
    bottom: 1rem;
    right: 1rem;
    background: var(--bg-tertiary);
    border: none;
    color: var(--text-primary);
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
    opacity: 0;
}

.text-area-wrapper:hover .copy-btn {
    opacity: 1;
}

.copy-btn:hover {
    background: var(--accent-color);
    transform: scale(1.05);
}