* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', sans-serif;
}

body {
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, #0f2027, #203a43, #2c5364);
    color: white;
    transition: 0.4s ease;
}

.container {
    width: 340px;
    padding: 30px;
    text-align: center;
    border-radius: 20px;
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(15px);
    box-shadow: 0 10px 40px rgba(0,0,0,0.4);
    animation: fadeIn 1s ease;
}

h1 {
    margin-bottom: 15px;
    letter-spacing: 1px;
}

#display {
    font-size: 38px;
    margin: 20px 0;
    letter-spacing: 2px;
    text-shadow: 0 0 10px rgba(255,255,255,0.4);
}

.buttons {
    margin-bottom: 10px;
}

.buttons button {
    padding: 10px 16px;
    margin: 5px;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s ease;
}

#startPause {
    background: linear-gradient(45deg, #00c853, #64dd17);
}

#lap {
    background: linear-gradient(45deg, #2979ff, #00b0ff);
}

#reset {
    background: linear-gradient(45deg, #d50000, #ff1744);
}

button:hover {
    transform: scale(1.1);
    box-shadow: 0 0 15px rgba(255,255,255,0.3);
}

#laps {
    margin-top: 15px;
    list-style: none;
    max-height: 140px;
    overflow-y: auto;
}

#laps li {
    padding: 6px;
    font-size: 13px;
    border-bottom: 1px solid rgba(255,255,255,0.2);
    animation: slideUp 0.3s ease;
}

.toggle {
    margin-top: 15px;
    font-size: 13px;
    cursor: pointer;
    opacity: 0.8;
}

.toggle:hover {
    opacity: 1;
}

/* Light Mode */
.light {
    background: linear-gradient(135deg, #e0eafc, #cfdef3);
    color: black;
}

.light .container {
    background: rgba(0,0,0,0.05);
}

/* Animations */
@keyframes fadeIn {
    from {opacity: 0; transform: translateY(20px);}
    to {opacity: 1; transform: translateY(0);}
}

@keyframes slideUp {
    from {opacity: 0; transform: translateY(10px);}
    to {opacity: 1; transform: translateY(0);}
}